Many efforts have been made in the past to produce plants from single cells. For example, British Patent Specification No. 1,387,821 discloses producing chemical plant metabolites by suspension culture and uses the process of organogenesis. The process is carried out by a sequential differentiation, in other words, by organs regeneration which occurs when the nutrient provided to the culture shows a decreasing auxin level.
The process can be schematically summarized: Explant callus cell clusters or single cells plant organ primordia.
"root primordia" PA1 "shoot primordia"p1 "pellet" PA1 the energy level produced by the light source provided to the culture; PA1 the spectrum of the provided light; PA1 the photoperiod; and PA1 the ambient temperature. PA1 the composition of the nutrients; PA1 the pH of the nutrients; and PA1 the O.sub.2 /CO.sub.2 ratio of the culture. PA1 (a) by culture of explants including the meristem of the shoot or the meristem of the root from the chosen plant which induces a callus. PA1 (b) from seeds by inducing the formation of a tumor. PA1 The mitotic cells are rejuvenated by the control of the above designated environmental factors. PA1 The embryonic cells under the chosen environment undergo differentiation and plant embryos, then seedlings are obtained with the understanding that the chosen stage or termination is according to the pursued goal: biochemical work or plant multiplicaton or plant improvement or other types of research or utilization such as chemicals, or food (protein) production. PA1 (1) a mixture of fluorescent "Atlas daylight" and incandescent tungsten filament lamps, PA1 (2) a mixture of fluorescent "Fluora" or "Gro lux" lamps and incandescent tungsten filament lamps, PA1 (3) Xenon lamps, PA1 (4) Iodine vapour lamps, PA1 (5) an equal combination of xenon lamps and iodine vapour lamps.
This regeneration taught by this publication is carried out under "subdued light" conditions with the temperature of the nutrient varying between 15.degree. C. and 35.degree. C. The process requires more than one year duration.
Metabolites such as tropane alkaloids are found in nature in various members of the plant family Solanaceae and Erythroxylaceae from which th first extractions occurred from Atropa belladonna and thus, the derivation of the alternative designation atropine group. The four main tropane alkaloids are atropine, hyoscine (scopolamine), hyoscyamine, (solanaceae) and cocaine (Erythroxylaceae).
The alkaloid atropine can be isolated from the plant deadly nightshade (Atropa belladonna ). The related alkaloid scopolamine (hyoscine) which has "truth drug" properties can be isolated from the plant species Scopolia spp. or Duboisia spp. Hyoscyamine can be isolated from plants of the species Hyoscyamus spp. The fourth main member of the tropane group alkaloids is cocaine and is mostly isolated from plants of the species Erythroxylon.
These alkaloids are also found in the plant Hyoscyamus niger,--which grows in Europe,--together with various other chemically related alkaloids of the group in minor amounts. However, the alkaloid content of Hyoscyamus niger is too low for commercial extraction. Although the yield of these alkaloids is not so low in plants of the tribe Daturae spp. these plants also are not used as raw material for commercial extraction.
The tropane alkaloids have well known medicinal properties. Indeed it is related that, as long ago as 1500 BC, plants producing alkaloids of the atropine group are used for criminal, magic or medicinal purposes. The tropane alkaloids are in demand not only by virtue of their own medicinal properties but also as starting materials for preparing other active compounds for use in medicine and in biological research.
Various members of the plant families Solanaceae and Erythroxylaceae are known to contain metabolites such as atropine, scopolamine, hyoscyamine, cocaine and related tropane alkaloids, more particularly plants of the species Hyoscyamus spp. Duboisia spp. and Erythroxylon spp. Besides Hyoscyamus niger mentioned above, there can also be mentioned Hyoscyamus muticus L. and Hyoscyamus aureus L. Hyoscyamus pusillus, Hyoscyamus albus, Withania, Solandra, and Anthocercis and Datura innoxia, Datura stra monium, Datura tatula, Datura meteloiides, Datura sanguinea.
Since the plants which are known to be rich in tropane alkaloids mostly originate from tropical or subtropical regions, current commercial methods of extracting atropine group alkaloids from natural sources rely on dried plant material as the raw material. Such dried material can be produced by oven-drying, for example at approximately 40.degree. C., or by freeze-drying. However this is a relatively inefficient and expensive method of obtaining the desired alkaloids since one must wait for the plant to reach maturity before harvesting and drying of the plant can take place. The yield of alkaloids is affected by the climatic and edaphic factors under which the crop is grown. In particular the crops prone to storm damage, storms being generally more frequent in the tropics than in the more temperate regions such as Europe, and such storm damage may tend to reduce the alkaloid content of the plants. Furthermore, the percentage of alkaloids in different crops of the same plant may vary considerably from year to year and from location to location due to differences, for example, in rainfall and in soil conditions under which the crop is grown. Moreover, the percentage of total alkaloids in the dried plant material may vary considerably at the time of extraction due to differences between chronological and physiological age, as well as to variations in storage conditions and in the conditions under which the harvested plants are transported.
In addition to the major tropane alkaloids discussed above, and minor alkaloids as example: littorine, hygrine, cuscohygrine, tigloidine, apohyoscine, noratropine, norhyoscine, apoatropine, and the tigloryl esters, other metabolites produced by plants have known value, exhibit worthwhile properties, or may prove valuable if an opportunity were available to collect significant quantities of same and to test. Therefore, a technique that would enhance the yield of any given metabolite or enable its creation in relatively short time frames would be welcome indeed. Also no one to date has been able to achieve embryogenesis in vitro related to production of physiologically active compound despite the extensive effort expended to date by the scientific community.